Cornea-supported artificial intraocular lens

ABSTRACT

Disclosed is an artificial intraocular lens attachable to the cornea. Made of a biocompatible material such as poly(methyl methacrylate), silica or acryl resin, the artificial intraocular lens comprises an asymmetrical optical part, two supports extended from opposite sides of the optical part; and plate- or ring-shaped, fixing parts having at least one hole, positioned at terminal parts of the supports.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to an artificial intraocular lens attachable to the cornea, which shows a desirable refraction index and causes almost no complications.

[0002] In order to better understand the background of the present invention, a description will be given of the eye in conjunction with FIG. 1. With reference to FIG. 1, there is shown an anatomy of the eye in a cross sectional view. In the eye, incident light beams are refracted mainly in a cornea 1 and lens 5 to form a focus on a retina 9 as in a camera, allowing the human to see an image or a scene. When becoming turbid for congenital or acquired reasons, the lens 5 cannot refract external light beams appropriately to form a focused image on the retina 9, which corresponds to a film in a camera. Serious turbidity of the lens 6 may result in losing one's sight.

[0003] When the lens is turbid to such a serious extent as to cause blindness, it is replaced with an artificial lens to recover the sight. In this regard, surgical insertion of an artificial lens in the eyeball is well known. For example, the anterior chamber angle, the ciliary body, or capsular lentis is the place where an artificial lens is inserted. In addition, an artificial lens may be supported to the iris 3.

[0004] However, some of the tissues, e.g. the iris, are anatomically so unstable that an artificial lens cannot be fixed thereto. For example, if an artificial lens is surgically transplanted to be supported by the iris, the patient may suffer from a complication. In addition, because the conventional sites in which an artificial lens is inserted are distant from the cornea, in which the greatest refraction of incident beams occurs, the actual refraction after the operation often does not agree with expected refraction.

SUMMARY OF THE INVENTION

[0005] Therefore, it is an object of the present invention to overcome the above problems encountered in prior arts and to provide an artificial intraocular lens, which can be supported by the cornea.

[0006] It is another object of the present invention to provide an artificial intraocular lens, which shows a desirable refraction index, can be firmly fixed to the cornea with little complications after surgical transplantation, and allows the liquid of the anterior chamber to flow so smoothly as to prevent the endothelial cells of the cornea from being damaged.

[0007] Based on the present invention, the above objects of the present invention could be accomplished by a provision of an artificial intraocular lens, which is supportable to the cornea and made of a biocompatible material, comprising: an asymmetrical optical part; two supports extended from opposite sides of the optical part; and plate- or ring-shaped, fixing parts having at least one hole, positioned at terminal parts of the supports.

BRIEF DESCRIPTION OF THE DRAWING

[0008]FIG. 1 is a diagram showing the structure of the eye.

[0009]FIG. 2 is a diagram showing the structure of the artificial, intraocular lens of the present invention.

[0010]FIG. 3 is a diagram after the artificial, intraocular lens of the present invention is applied to the eye.

DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention pertains to an artificial intraocular lens that can increase the refraction of incident beams to a satisfactory level, be fixed firmly enough to prevent the occurrence of complications, and allow the liquid of anterior chamber to smoothly flow to prevent the damage of corneal endothelial cells.

[0012] The artificial intraocular lens of the present invention is made of a biocompatible material. Suitable as such a biocompatible material is poly(methyl methacrylate), silica or acrylic resin. Since its biocompatibility as an ocular material through elution tests and biological assays in the 1940s, poly(methyl methacrylate) has been extensively used.

[0013] With reference to FIG. 2, there is illustrated the artificial intraocular lens of the present invention. As seen in this figure, the artificial intraocular lens comprises an asymmetrical optical part 1 a, two supports 1 b extended from opposite sides of the optical part 1 a, and plate- or ring-shaped, fixing parts 1 c having at least one hole 1 d, positioned at terminal parts of the supports 1 b. The asymmetrical design of the optical part 1 a is to allow the smooth covection current of the liquid of the anterior chamber. In detail, as seen in FIG. 2, the optical part has a truncated circle shape.

[0014] To opposite sides of the intraocular lens optical part 1 a are fixed two supports 1 b at terminal sites of which plate- or ring-shaped fixing parts 1 c are provided.

[0015] The supports 1 c are inserted to either the cornea or the parenchyma between the cornea and the corneosclera and fixed thereat, firmly supporting the artificial intraocular lens to the cornea.

[0016] At least one hole 1 d is provided to the supports 1 c, playing a role in firmly fixing the supports 1 c to the cornea or the parenchyma between the cornea and the corneosclera.

[0017] After the supports 1 c are inserted into the corneal parenchyma by a surgical operation, corneal cells can grow through the support holes 1 d, so that the optical part 1 c can be firmly fixed to the cornea or the parenchyma between the cornea and the corneosclera. FIG. 3 shows the application of the artificial intraocular lens of the present invention to the eye.

[0018] Because the artificial intraocular lens of the present invention is designed to be fixed to the cornea or the corneosclera, which contributes most to the refraction index of the eye, in addition to being an anatomically stable tissue, not only can incident beams be refracted to a desired angle, but only minimal complications, if any, occur.

[0019] Additionally, the optical part 1 a has an asymmetrical shape like a truncated circle, so that, when the artificial intraocular lens is applied to the eyeball, the liquid of the anterior chamber can flow smoothly without damage to the endothelial cells of the cornea.

[0020] A better understanding of the present invention may be obtained in light of the following examples which are set forth to illustrate, but are not to be construed to limit the present invention.

EXAMPLE 1

[0021] Ketamine and xylazine each were administered to New Zealand rabbits weighing about 3 kg at a dose of 50 mg/kg by intramuscular injection at the posterior. When no responses were obtained after irritation of eye rims of the rabbits, each of them was fixed on a board in which nails were previously driven according to a rabbit contour.

[0022] 1% proparacaine was dropped in the eyes for complete anaesthesia, after which the eye rims were sterilized with a 10% providone solution. 6-0 black silk sutures were passed through the extraocular muscle of the eyes to fix the eyes. Using a diamond dissector, the cornea was opened, after which the artificial intraocular lens of the present invention was inserted into the opened site which was then sutured.

[0023] An observation was continuously made of the behavior of the rabbits for 7 days in a breeding room after they came out of the anesthetic. At one week, one month and three months after the operation, the eyeballs were removed from the rabbits and fixed in formalin. Microscopic observation of the eye tissue indicated that the artificial intraocular lens of the present invention was firmly fixed to the cornea and had generated no complications nor damage to the endothelial cells of the cornea.

[0024] As described hereinbefore, the artificial intraocular lens of the present invention is fixed to the parenchyma of the cornea or the corneosclera, which contributes most of the refractive index of the eyeball and is an anatomically stable tissue, unlike the iris, such that there can be brought about effects of increasing the refraction of incident beams to a desirable level and minimizing post-operation complications. Additionally, the asymmetrical shape of the artificial intraocular lens allows smooth covection of the liquid of the anterior chamber, preventing the endothelial cells of the cornea from being damaged. Furthermore, the holes provided to the supports serve to firmly fix the artificial intraocular lens to corneal parenchyma.

[0025] The present invention has been described in an illustrative manner, and it is to be understood that the terminology used is intended to be in the nature of description rather than of limitation. Many modifications and variations of the present invention are possible in light of the above teachings. Therefore, it is to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. 

What is claimed is:
 1. A cornea-supported artificial intraocular lens, made of a biocompatible material, comprising: an asymmetrical optical part; two supports extended from opposite sides of the optical part; and plate- or ring-shaped, fixing parts having at least one hole, positioned at terminal parts of the supports.
 2. The cornea-supported, artificial intraocular lens as set forth in claim 1 , wherein the biocompatible material is selected from the group consisting of poly(methyl methacrylate), silica, and acryl resin.
 3. The cornea-supported, artificial intraocular lens as set forth in claim 1 , wherein the asymmetrical optical part has a truncated circular shape. 